Answer:a) Public sector
Explanation: Public sector is the department that comes under the government. The public coming under the public sector fulfill the functions of the public services.The employees working for these sectors are known as public employees or servant.They work in the various departments like transportation, medical,infrastructure etc.
Public sector people get salaries by the taxes that are generated from the country people tax payers. Other options are incorrect because they don't work as the government body and get paid by the different sources rather than tax.Thus the correct option is option (a).